Vortex Viper spotting scopes are offering outstanding clear and high contrast image manly because of their build quality. The small light dispersion and excellent optical properties are achieved with XD glass, from which the lenses are made. The high accurate manufactured lenses are covered with high quality multilayer coatings, which assure high contrast, rich colours and high resolution image. Also the XR lens coatings are used to increase the light transmission rate and enable the low light condition or dusk usage. The spotting scopes are sealed with o-rings which make them fully waterproof and at the same time they are filled with dry nitrogen. That makes the use at low temperature environment or under the rain, carefree. The lenses are also protected from dirt, water and small damages with special high resistant outer coating.